Use the correct group for JIT constraints.

This fixes a rare crash/CTD in JS.
This adds information about the constraints to a new RAII class so we
can finish all constraints at the end.
Based on changes in BZ 1568397

2 files changed, 136 insertions, 7 deletions

diff --git a/js/src/vm/TypeInference.cpp b/js/src/vm/TypeInference.cpp
index 7c2c0194e..88327b47e 100644
--- a/js/src/vm/TypeInference.cpp
+++ b/js/src/vm/TypeInference.cpp
@@ -3084,29 +3084,39 @@ class TypeConstraintClearDefiniteGetterSetter : public TypeConstraint
 };
 
 bool
-js::AddClearDefiniteGetterSetterForPrototypeChain(JSContext* cx, ObjectGroup* group, HandleId id)
+js::AddClearDefiniteGetterSetterForPrototypeChain(JSContext* cx,
+                                                  DPAConstraintInfo& constraintInfo,
+                                                  ObjectGroup* group,
+                                                  HandleId id,
+                                                  bool* added)
 {
     /*
      * Ensure that if the properties named here could have a getter, setter or
      * a permanent property in any transitive prototype, the definite
      * properties get cleared from the group.
      */
+     
+    *added = false;
+    
     RootedObject proto(cx, group->proto().toObjectOrNull());
     while (proto) {
         ObjectGroup* protoGroup = JSObject::getGroup(cx, proto);
         if (!protoGroup) {
-            cx->recoverFromOutOfMemory();
             return false;
         }
         if (protoGroup->unknownProperties())
-            return false;
+            return true;
         HeapTypeSet* protoTypes = protoGroup->getProperty(cx, proto, id);
-        if (!protoTypes || protoTypes->nonDataProperty() || protoTypes->nonWritableProperty())
+        if (!protoTypes)
             return false;
-        if (!protoTypes->addConstraint(cx, cx->typeLifoAlloc().new_<TypeConstraintClearDefiniteGetterSetter>(group)))
+        if (protoTypes->nonDataProperty() || protoTypes->nonWritableProperty())
+            return true;
+        if (!constraintInfo.addProtoConstraint(proto, id))
             return false;
         proto = proto->staticPrototype();
     }
+    
+    *added = true;
     return true;
 }
 
@@ -3612,6 +3622,43 @@ struct DestroyTypeNewScript
 
 } // namespace
 
+bool DPAConstraintInfo::finishConstraints(JSContext* cx, ObjectGroup* group) {

+  for (const ProtoConstraint& constraint : protoConstraints_) {

+    ObjectGroup* protoGroup = constraint.proto->group();

+

+    // Note: we rely on the group's type information being unchanged since

+    // AddClearDefiniteGetterSetterForPrototypeChain.

+

+    bool unknownProperties = protoGroup->unknownProperties();

+    MOZ_RELEASE_ASSERT(!unknownProperties);

+

+    HeapTypeSet* protoTypes =

+        protoGroup->getProperty(cx, constraint.proto, constraint.id);

+    MOZ_RELEASE_ASSERT(protoTypes);

+

+    MOZ_ASSERT(!protoTypes->nonDataProperty());

+    MOZ_ASSERT(!protoTypes->nonWritableProperty());

+

+    if (!protoTypes->addConstraint(

+            cx,

+            cx->typeLifoAlloc().new_<TypeConstraintClearDefiniteGetterSetter>(

+                group))) {

+      ReportOutOfMemory(cx);

+      return false;

+    }

+  }

+

+  for (const InliningConstraint& constraint : inliningConstraints_) {

+    if (!AddClearDefiniteFunctionUsesInScript(cx, group, constraint.caller,

+                                              constraint.callee)) {

+      ReportOutOfMemory(cx);

+      return false;

+    }

+  }

+

+  return true;

+}

+
 bool
 TypeNewScript::maybeAnalyze(JSContext* cx, ObjectGroup* group, bool* regenerate, bool force)
 {
@@ -3715,10 +3762,17 @@ TypeNewScript::maybeAnalyze(JSContext* cx, ObjectGroup* group, bool* regenerate,
         return false;
 
     Vector<Initializer> initializerVector(cx);
+    
+    DPAConstraintInfo constraintInfo(cx);
 
     RootedPlainObject templateRoot(cx, templateObject());
     RootedFunction fun(cx, function());
-    if (!jit::AnalyzeNewScriptDefiniteProperties(cx, fun, group, templateRoot, &initializerVector))
+    if (!jit::AnalyzeNewScriptDefiniteProperties(cx,
+                                                 constraintInfo,
+                                                 fun,
+                                                 group,
+                                                 templateRoot,
+                                                 &initializerVector))
         return false;
 
     if (!group->newScript())
@@ -3772,6 +3826,14 @@ TypeNewScript::maybeAnalyze(JSContext* cx, ObjectGroup* group, bool* regenerate,
         // The definite properties analysis found exactly the properties that
         // are held in common by the preliminary objects. No further analysis
         // is needed.
+

+        if (!constraintInfo.finishConstraints(cx, group)) {

+            return false;

+        }

+        if (!group->newScript()) {

+            return true;

+        }

+
         group->addDefiniteProperties(cx, templateObject()->lastProperty());
 
         destroyNewScript.group = nullptr;
@@ -3792,6 +3854,16 @@ TypeNewScript::maybeAnalyze(JSContext* cx, ObjectGroup* group, bool* regenerate,
                                                                   initialFlags);
     if (!initialGroup)
         return false;
+

+    // Add the constraints. Use the initialGroup as group referenced by the

+    // constraints because that's the group that will have the TypeNewScript

+    // associated with it. See the detachNewScript and setNewScript calls below.

+    if (!constraintInfo.finishConstraints(cx, initialGroup)) {

+        return false;

+    }

+    if (!group->newScript()) {

+        return true;

+    }

 
     initialGroup->addDefiniteProperties(cx, templateObject()->lastProperty());
     group->addDefiniteProperties(cx, prefixShape);
diff --git a/js/src/vm/TypeInference.h b/js/src/vm/TypeInference.h
index 94ce7e871..fd021fc96 100644
--- a/js/src/vm/TypeInference.h
+++ b/js/src/vm/TypeInference.h
@@ -789,8 +789,65 @@ class TemporaryTypeSet : public TypeSet
                                  TypedArraySharedness* sharedness);
 };
 
+// Stack class to record information about constraints that need to be added
+// after finishing the Definite Properties Analysis. When the analysis succeeds,
+// the |finishConstraints| method must be called to add the constraints to the
+// TypeSets.
+//
+// There are two constraint types managed here:
+//
+//   1. Proto constraints for HeapTypeSets, to guard against things like getters
+//      and setters on the proto chain.
+//
+//   2. Inlining constraints for StackTypeSets, to invalidate when additional
+//      functions could be called at call sites where we inlined a function.
+//
+// This class uses bare GC-thing pointers because GC is suppressed when the
+// analysis runs.
+class MOZ_RAII DPAConstraintInfo {
+  struct ProtoConstraint {
+    JSObject* proto;
+    jsid id;
+    ProtoConstraint(JSObject* proto, jsid id) : proto(proto), id(id) {}
+  };
+  struct InliningConstraint {
+    JSScript* caller;
+    JSScript* callee;
+    InliningConstraint(JSScript* caller, JSScript* callee)
+        : caller(caller), callee(callee) {}
+  };
+
+  JS::AutoCheckCannotGC nogc_;
+  Vector<ProtoConstraint, 8> protoConstraints_;
+  Vector<InliningConstraint, 4> inliningConstraints_;
+
+public:
+  explicit DPAConstraintInfo(JSContext* cx)
+      : nogc_(cx)
+      , protoConstraints_(cx)
+      , inliningConstraints_(cx)
+  {
+  }
+
+  DPAConstraintInfo(const DPAConstraintInfo&) = delete;
+  void operator=(const DPAConstraintInfo&) = delete;
+
+  MOZ_MUST_USE bool addProtoConstraint(JSObject* proto, jsid id) {
+    return protoConstraints_.emplaceBack(proto, id);
+  }
+  MOZ_MUST_USE bool addInliningConstraint(JSScript* caller, JSScript* callee) {
+    return inliningConstraints_.emplaceBack(caller, callee);
+  }
+
+  MOZ_MUST_USE bool finishConstraints(JSContext* cx, ObjectGroup* group);
+};
+
 bool
-AddClearDefiniteGetterSetterForPrototypeChain(JSContext* cx, ObjectGroup* group, HandleId id);
+AddClearDefiniteGetterSetterForPrototypeChain(JSContext* cx,
+                                              DPAConstraintInfo& constraintInfo,
+                                              ObjectGroup* group,
+                                              HandleId id,
+                                              bool* added);
 
 bool
 AddClearDefiniteFunctionUsesInScript(JSContext* cx, ObjectGroup* group,